The confection of hard or soft ice cream and frozen yogurt deserts has become very popular in the past years. More recently, some attempts have been made to offer soft serve ice cream in a large selection of flavors as is available for hard frozen ice cream and frozen yogurt, but with very limited success. Indeed, the addition of fruits or liquid flavoring tends to increase the temperature and density of the product. This has no significant drawbacks for hard ice cream since the product is cooled after preparation and the initial air content, usually higher than for soft ice cream, can be adjusted accordingly in the initial steps of the preparation process. Similarly, a yogurt based frozen confection is prepared from hard and frozen portions to which fruits or concentrated flavors are incorporated by mixing. The average temperature and air content (overrun) are thus increased with respect to the base hard frozen product. To obtain a soft mixture with the expected texture and consistence that mixture is then extruded from the mixing chamber to form the final product. Such a process is accomplished by a homogenization or yogurt machine with combined chopping, mixing and extruding functions of the type described in U.S. Pat. No. 4,668,561 (Ney, 1987), No. 4,861,255 (Ney, 1989) and 5,208,050 (Ney, 1993). It is also known to use such an apparatus to prepare a serving of flavored soft ice cream from a serving of hard ice cream with addition of fruits, liquid flavoring, nuts and the like.
A recent attempt to widen the spectrum of available flavors for the preparation of stripped or twisted confections is described in U.S. Pat. No. 5,743,640 (Crossley, 1998).
Experience with this type of equipment tends to prove poor performance, the prepared confections being small, compact and rapidly melting for a given weight of ice cream. These confections cannot be dipped in coatings such as chocolate, caramel, nuts or candies.
From that survey of above methods and equipment of the prior art, it becomes obvious that they fail at responding to the market need for a soft ice cream confection of good quality in a plurality of custom selectable flavors in a simple and economical manner.
The limitation of the prior art is that the current state of the art is far from permitting of a striped soft ice cream confection incorporating two or more custom prepared flavors, with the possibility of adding solid or high density ingredients to the individual flavored ice cream streams or hidden in the centre of the confection.